System Log

What Does System Log Mean?

The system log (syslog) contains a record of the operating system (OS) events that indicates how the system processes and drivers were loaded. The syslog shows informational, error and warning events related to the computer OS. By reviewing the data contained in the log, an administrator or user troubleshooting the system can identify the cause of a problem or whether the system processes are loading successfully.


Techopedia Explains System Log

The OS maintains a log of events that helps in monitoring, administering and troubleshooting the system in addition to helping users get information about important processes. Some of the events include system errors, warnings, startup messages, system changes, abnormal shutdowns, etc. This list is applicable to most versions of the three common OSs (Windows, Linux and Mac OS).

The events recorded are the significant occurrences in the OS that require notifying the user. The log contains information about the software, hardware, system processes and system components. It also indicates whether the processes loaded successfully or not. The information can then be used to diagnose the sources of computer problems, whereas the warnings can be used to predict potential system issues and problems.

The syslog has standard components that may vary depending on the OS. However, there are common components and information that are captured regardless of the OS.

All entries are classified by type such as error, information, warning, success audit and failure audit for Windows systems, and emergency, alert, critical, error, warning, notice, info and debug for Mac OS and Linux systems.

Each syslog entry contains a header information and a description of the events. The latter includes the date and time the events occurred, the username logged on and the computer name at the time of the event. It also contains the event ID number that is used to identify the event and the source of the event such as the name of the system component.

The syslog is easily viewed using built-in utilities such as the Event Viewer in Windows. In addition to viewing, the Event Viewer is also used to manage the file size, save or archive the log file, clear old events and set overwrite options. Other options include finding or filtering events and restoring the log to default settings.


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Margaret Rouse

Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…